Oddly enough, the cabin service people on the plane are constantly eating during the night, helping themselves to the first-class snacks. They are bulging out of their uniforms. They cannot pass each other in the aisles without difficulty. This is the sort of thing you notice during a long flight; at least the sort of thing I notice. I arrive in the morning at Johannesburg after an 11-hour flight from Heathrow, to promote my new book, Up Against the Night. I am met by a minder who turns out to be the wife of an admiral in the South African navy. He is stationed in Pretoria. I point out that there is no naval base within a thousand miles of Pretoria. She says her husband has noticed this.

The book tour is a strange institution. You are wheeled about to explain your book, and even to justify it. I know from experience that many of the people who come to hear me will think of themselves as being under siege; their children have long ago gone to Australia and New Zealand and Canada. In Johannesburg I don’t meet a single African journalist. I am driven to a very luxurious hotel in Houghton, not far from where Nelson Mandela lived after his release. He was often lonely, and Nadine Gordimer, who lived not far away, told me he invited himself for dinner. This landscape is familiar to me; we lived nearby. Not many people like Johannesburg, but I love the place. I look at the barbed wire threaded along the garden walls of every house. I recognise the bird song and feel the morning cold and I am caught up in nostalgia.

The hotel is staggeringly luxurious. It was once a huge private house. There are shortbreads in every room and jars of biltong and hillocks of white towels, flowers everywhere, and the breakfasts are Homeric. Yet there is almost no one but me in residence. Large black-and-white birds, the hah-di-dahs, stalk the lawns. They have crescent beaks, which they use to dig up worms and insects. When they are fed up, which is often, they make a raucous complaint and take to the air. It is a startling racket, more strident than melodic. These birds — they are ibis of a sort — migrated some years ago to the lush and watered suburbs from their original homes, which were miles away in places like the Okavango Swamps.

In the long hours of travelling and waiting, I read R.W. Johnson’s book, How Long Will South Africa Survive? He offers a chilling analysis: ‘Twenty years of ANC rule have shown conclusively that the party is hopelessly ill equipped for this task. Indeed, everything suggests that South Africa under the ANC is fast slipping backward and that even the survival of South Africa as a unitary state cannot be taken for granted…. it is now clear that South Africa can either choose to have an ANC government or it can have a modern industrial economy. It cannot have both.’ Johnson, a South African, a friend of mine and an emeritus fellow of Magdalen College, Oxford, was never susceptible to the delusion of the Rainbow Nation; he exposed corruption and ineptitude from the start.

The plane approaches Cape Town and, as always, I am astonished by the view of Table Mountain and the surrounding sea. It is so overwhelmingly beautiful that I feel the urge to belong, not necessarily to the people, but to the landscape. I was taken by Robert Macfarlane’s suggestion that landscape can be internalised, and am susceptible to the idea that the landscape can be a part of one’s basic make-up.

The Fugard Theatre is the creation of Eric Abraham, the film and theatre producer; now it is the centre of the Open Book festival. It is on the edge of what was the multicultural and vibrant District Six, maliciously razed by the Nationalist government in the 1960s and never rebuilt. The theatre has become a important venue for theatre and music and film. Eric had the Donmar Warehouse in mind when he and his architects planned it. Now it is lively, with events going on day and night. I am staying in a nearby hotel. There are two or three criminal courts up the road and as I walk to the theatre, I see prisoners being taken from one building to another in handcuffs. The guards are all obese, the prisoners thin. Some onlookers shout up at their relatives in the direction of the cells, and voices shout back. They speak to each other in Cape Afrikaans.

I manage to get away for half a day, walking on my favourite beach. Too cold to swim, alas, but the surfers are out and the view of the enormous rocks and the pounding sea are almost as therapeutic as a swim. I feel a pull when I have to leave. Although I haven’t lived in South Africa since I was a boy, I think about it every day.

Back home after my tour, I am happy to go to Wolfson College, Oxford, for the launch of the final volume of Henry Hardy’s and Mark Pottle’s labours. They have edited the final volume of Isaiah Berlin’s Affirming: Letters 1975–1997. I have worshipped Berlin from the day I read ‘Two Concepts of Liberty’ in South Africa. It seemed to make it respectable to be a liberal. Shortly before he died, a Polish researcher asked Berlin what the meaning of life was. In a world beset by violent strife in the name of some religious belief, Berlin’s reply is a manifesto of common sense:

As for the meaning of life, I do not believe that it has any: I do not at all ask what it is, for I suspect it has none, and this is a source of great comfort to me — we make of it what we can, and that is all there is about it. Those who seek for some deep, cosmic, all-embracing, teleologically arguable libretto or god are, believe me pathetically deluded.

‘We make it what we can.’ I find this deeply moving in its simplicity.